1. Technical Field
The present invention relates to a color filter substrate, an electro-optic device including the color filter substrate, and an electronic apparatus including the electro-optic device.
2. Related Art
When a color image is displayed in an electro-optic device such as a liquid crystal device, a color filter substrate in which a color filter layer is formed on one surface of a light-transmissive substrate is used as a counter substrate. Further, a color filter substrate is also used in an electro-optic device such as an organic electroluminescence device. In the color filter substrate, as shown in FIG. 8A, light-shielding protrusion portions 29t called a so-called black matrix or black stripe are formed between pixels and color filter layers 28 are formed in the regions partitioned by the light-shielding protrusion portions 29t in order to prevent color mixing between the adjacent pixels (sub-pixels).
To increase the chromaticity of the color filter layers 28 in the color filter substrate, the color filter layers 28 have to be formed thickly. In this case, the light-shielding protrusion portions 29t have to be formed so as to be thick. However, when the light-shielding protrusion portions 29t are formed by forming metal films in accordance with a sputter method, it takes a lot of time to form the films. Accordingly, a technique of forming the light-shielding protrusion portions 29t using a black photosensitive resin layer has been suggested (see JP-A-2003-270431).
However, exposure accuracy is low in the case of the black photosensitive resin. Therefore, when pixels are miniaturized for high accuracy of display, it is difficult to form the light-shielding protrusion portions 29t in the black photosensitive resin layer so as to correspond to the miniaturization of the pixels.
Here, as shown in FIG. 8B, the inventors have examined a technique of forming the light-shielding protrusion portions 29s by light-transmissive layers 291s formed by a CVD method or a coating method and metal-based light-shielding layers 292s formed of a metal, a metal compound, or the like laminated on the light-transmissive layers 291s and providing the color filter layers 28 inside the regions partitioned by the light-shielding protrusion portions 29s. With such a configuration, since the light-transmissive layers 291s can be formed by a CVD method or a coating method, the thick light-shielding protrusion portions 29s can be efficiently formed. Further, a metal oxide layer can be formed with high accuracy by a photolithography technique unlike the black photosensitive resin layer. Therefore, since a light-transmissive photosensitive resin layer can be exposed with high accuracy unlike the black photosensitive resin layer, the light-transmissive photosensitive resin layer can be formed so as to correspond to the miniaturization of the pixels. The configuration shown in FIG. 8B is a reference example disclosed to compare with the configuration of the invention and is not a configuration of a related art.
In the configuration shown in FIG. 8B, however, a problem may arise in that since the light-transmissive layer 291s is present on the lower layer of the light-shielding protrusion portion 29s, diagonally travelling light passes through the adjacent color filter layer 28, as indicated by an arrow L0, and thus a mixed color occurs.